Device for maintaining a locked and closed state of a space-separating device in a releasable manner

ABSTRACT

The invention relates to a device ( 1 ) for maintaining a locked and closed state of a space-separating device ( 2 ) in a releasable manner, in particular a protective device of a machine ( 4 ) having a first part ( 6 ) with an opening and a second part ( 8 ), said parts being movable relative to one another, the opening therefore being at least partially closable, wherein the device ( 1 ) comprises a latch ( 18 ) by means of which the closed state of the space-separating device ( 2 ) may be locked, a holding element ( 30 ) by means of which the latch ( 18 ) may be kept in the latched position, and a release element ( 36 ) by means of which the catch of the latch ( 18 ) may be released, and wherein the catch of the latch ( 18 ) may be lifted by a rotational movement of the release element ( 36 ) relative to the latch ( 18 ).

This invention relates to a device for maintaining a locked and closedstate of a space-separating device in a releasable manner, in particularthe protective device of a machine.

In production engineering, for example, among other things, for safetyreasons, machines and systems are set up within a space which isseparated from the exterior and in which a person is not permitted toremain during operation of the machine. But in order, for example, tohave access to the machine for maintenance work, the space-separatingdevice generally has a closable opening. Generally speaking, operationof the machine conversely should only be possible when the opening isclosed and the closed state is locked. Access to the machine is onlypossible when the locking of the closed state is neutralized.

DE 203 15 959 U1 discloses a device for monitoring the state of such aspace-separating device, in which it is ensured that a person locatedwithin the separated space is not able to close the space-separatingdevice and lock it from the inside since otherwise there would be therisk that the machine could started inadvertently or intentionally whilea person is located within the space-separating device.

DE 196 32 962 A1 discloses a door actuation device by means of whichfrom the interior of the space-separating device a latch which locks theclosed state can be transferred into its unlocking position, and thusthe space-separating device can be opened, but conversely the latchcannot be transferred into its locking position, however, this beingpossible only from the outside. In this way a type of “escape unlocking”is implemented.

DE 10 2005 057 108 A1, which was published at a later date, discloses asafety switch for producing a release signal depending on the positionof a movable protective door. The part which is to be attached to theprotective door has an actuator which can be moved between a first and asecond position. The part which is to be attached to the frame has arecess which the actuator in the second position can engage.Furthermore. there is a blocking element to block the actuator in thesecond position.

DE 298 24 200 U1 discloses a device which enables an individual who isinadvertently locked within the protective enclosure to leave thisprotective enclosure. At the same time, the machines which are locatedwithin the protective enclosure can only be operated when the door onwhich the device is located is not only closed, but locked.

The object of this invention is to provide a generic device whichovercomes the disadvantages of the prior art. In one embodiment thedevice is intended to enable not only locking of the closed state of thespace-separating device, but, moreover, maintaining the locked andclosed state, for example, as long as the machine located within thespace-separating device is in an operating state which is hazardous topeople, for example, when the machine is running down after it has beenturned off. In one embodiment, in spite of maintaining the locked andclosed state, it is to be possible for the locking of the latch to beneutralized from within the space-separating device. The device isintended to ensure permanently reliable and safe operation.

The object is achieved by the device specified in claim 1. Specialembodiments are specified in the dependent claims.

The space-separating device can be in particular protective hoods,protective doors, or also an arrangement of partitions or separatinggratings by which the inner region around a machine, such as a machinetool or an industrial robot, is separated from an outer region in whichindividuals can remain even during operation of the machine. The firstpart of the space-separating device can be designed, for example, as aframe part, while conversely, a second part such as, for example, a dooror window is movable. In the case of a door, conventionally the secondpart is pivotally coupled to the first part or is movably guidedthereon.

The device has a latch by means of which the closed state of thespace-separating device can be locked. In one embodiment the latch ismovably supported in the device and can be transferred from theretracted position into the locking position by means of an actuationelement, such as a knob, and thus can engage a latch receiver byblocking it and can lock the closed state. By means of the holdingelement the latch can be blocked in its locking position and thus thelocked and closed state of the protective device can be blocked andmaintained closed.

One or more sensors can detect the closed state of the protectivedevice, locking of the closed state and/or maintaining the locked andclosed state and can signal it to a device which controls the machine.It can be established, for example, by this control that the machine canbe started only when the space-separating device is closed, the closedstate is locked and/or the locked and closed state is blocked. Theblocking and/or the neutralization of the blocking can take placelikewise in a signal-controlled manner, for example, the control canprovide for the blocking of the latch to be neutralized only when themachine is in the safe state, for example, a machine tool or anindustrial robot is stopped, so that it cannot pose a danger to people.The blocking and/or release can be driven in a controlled manner forthis purpose.

In one embodiment the holding element is spring-loaded and can, forexample, engage the latch and block it as soon as the latch and holdingelement have sufficiently approached one another. The blocking can alsobe neutralized by a controllable drive, for example, by means of anelectromagnet or a piezoelectric drive. Alternatively, the holdingelement can also be kept spring-loaded in a non-blocking position andcan be transferred by a drive into the state which blocks the latch inits locking position. In another alternative embodiment, the holdingelement can also have two stable states between which is it possible toswitch back and forth by means of a drive.

The device moreover has a release element by means of which the blockingof the latch can be neutralized. It is to be possible to actuate thisrelease element from the inside of the space-separating device,optionally even against the action of a driving or spring force whichacts on the holding element. This ensures that a person located withinthe space-separating device is easily able, in particular withoutactuating an EMERGENCY OFF button, to neutralize the maintaining of thelocked and closed state. Optionally, by neutralizing the blocking of thelatch the device can produce a signal which signals to be machinecontrol that the machine is to be transferred into the safe operatingstate, for example, is to be turned off.

The blocking of the latch can be neutralized by the rotary motion of therelease element relative to the latch. In one embodiment the releaseelement is located pivotally supported on the latch for this purpose.Reliable neutralization of the blocking of the latch thus can be enabledwith simple mechanical elements.

In one embodiment, following the rotary motion, the release elementtogether with the latch can be moved and thus the locked and closedstate of the space-separating device can also be neutralized, whereuponthe space-separating device can be opened. In one embodiment theactuating element located within the space-separating device dictatesdynamic coupling in only one direction, specifically in the direction ofneutralizing the locking position of the latch, conversely in the otherdirection there is trip-free mechanism which prevents the positionlocated within the space-separating device from being able to transferthe latch into is locking position.

In one embodiment the release element is a dual-arm lever which can beturned around an axis of rotation. The configuration as a dual-arm levercan implement different force and path ratios, for example, a relativelyhigh torque for neutralizing the blocking of the latch can be madeavailable with comparatively small actuating forces. Conversely, acorrespondingly large lever arm can make available a comparatively largepath, for example, for lifting the holding element out of a catchdepression and thus for neutralizing the blocking of the latch.Moreover, the interval between delivering the force for neutralizing theblocking of the latch on the one hand and the position of the lever incontact with the holding element on the other hand can be chosen to belarge. In this way the mechanical elements which are necessary foractuation can be located within the device such that the design issmall. Alternatively or in addition, the actuating elements which arelocated on the inside and outside for neutralizing the blocking of thelatch on the one hand and the actuating elements provided fortransferring the latch into its locking position on the other can belocated at a distance to one another; this is especially advantageousfor some applications.

In one embodiment the release element can be actuated by means of aknob. The initial rotary motion of the knob at the outset results inrotary motion of the release element with which the locking of the latchcan be neutralized. As turning continues there is linear motion of thelatch out of the locked position.

The release element can be turned, for example, by means of an elementwhich is movably supported in the device and which is connected to thefirst knob by way of a coupling device. The coupling device in this caseconverts the rotary motion of the first knob by 90° into linear motionof the displacement element. For this purpose the coupling device canhave a first and second lever which are hinged to one another at anarticulation point as a hinged joint. The first lever is nonrotatablyconnected to the first knob. The second lever is connected directly orindirectly to the displacement element by way of other elements. Whenthe first lever is turned, the displacement element is moved. As aresult first the blocking of the latch can be neutralized and then thelatch can be guided out of its locking position. In the reversedirection there is no motion coupling between the displacement elementand the latch, in particular not with respect to linear motion.

In one embodiment the device has a second knob which can be actuatedfrom the outside of the space-separating device, specifically located onthe outside of the device. By means of the second knob, the latch can bemoved into its position which locks the closed state. In one embodimentthe axes of rotation of the first and second knob have an offset to oneanother. On the one hand, this has the advantage that each part of thespace-separating device to which the device is attached need not beprovided with a through hole for the common axis of rotation of the twoknobs, as is necessary in the prior art; this metal-cutting at theinstallation site is disadvantageous for many reasons. On the otherhand, the offset of the two axes of rotation ensures that in the closedstate of the space-separating device there are no light gaps which aredisadvantageous especially when within the space-separating device thereis a laser machining device and the emergence of laser light from thespace-separating device must be reliably prevented.

In one embodiment the latch and/or the holding element are made suchthat they positively engage one another in the position which blocks thelatch. For example, the latch can have a recess with a catch flank inwhich the holding element catches in the position which blocks thelatch. The positive locking ensures that the resulting self-locking canimplement a high holding force without correspondingly high drive forceshaving to be made available by a motor. This is especially advantageousbecause the release element optionally must overcome those forces whichactivate the holding element.

In one embodiment, the device has a first sensor by means of which theposition of the latch which locks the closed state of thespace-separating device can be signaled. The first sensor can be asafety switch as is conventionally used in safety engineering. Inaddition to contact safety switches in which a mechanically encodedactuator is introduced into the switch head and triggers a switchingprocess there, so-called non-contact or electronic safety switches canalso be used which wirelessly transmit signals between an actuator and aread head. In one embodiment there is an actuator in the form of atransponder on the latch and in the position which locks the closedstate of the space-separating device the actuator moves into theresponse region of a read head so that only in the position of the latchwhich locks the closed state of the space-separating device is signaltransmission between the read head and the transponder possible. In oneembodiment the transponder is located near the jacket surface of thelatch and the read head is located near or on the wall of the pertinentlatch receiver. Alternatively, the actuator can also be located on ornear the face-side end of the latch.

In one embodiment the device has a second sensor by means of which theposition of the holding element which blocks the latch can be signaled.This second sensor can also be made generally as a non-contact safetyswitch. The holding element could be made specifically as a couplingelement, for example, for signal coupling between the transponder whichis located on the latch and the read head. Fundamentally, the first andthe second sensor can be made separately. Alternatively, it is possibleby means of the holding element to couple the transponder of the firstsensor to a second read head of the second sensor so that there would beonly one transponder on the latch. In this case it would also bepossible to separately detect whether the latch is in its blockingposition and whether the locked position is blocked by the holdingelement. In another alternative, signal coupling between the transponderand read head of the first sensor could only be possible when theholding element is in its position which blocks the latch.

In one embodiment, the second sensor is an optical or magnetic sensor,such as a photoelectric barrier or a Hall sensor. Sensors such as thesecan be easily configured in a small design and optionally also directlyon a circuit board. The holding element can be made as a pivotablelever, with a catch projection which is located at a distance from theaxis of rotation for interaction with the lock.

Other advantages, features and details of the invention will becomeapparent from the dependent claims and the following description inwhich with reference to the drawings embodiments of the invention aredetailed. In this connection, the features referred to in the claims andin the specification can each be essential for the inventionindividually by themselves or in any combination.

FIG. 1 shows a schematic top view of one embodiment of a deviceaccording to the invention,

FIG. 2 shows an enlarged cutaway view of the embodiment,

FIG. 3 shows an enlarged cutaway view of the embodiment,

FIG. 4 shows an enlarged cutaway view of the embodiment, and

FIG. 5 shows a side view of the device.

FIG. 1 shows a schematic top view of one embodiment of the device 1according to the invention for maintaining the locked and closed stateof the space-separating device 2, in particular the protective device ofa machine 4, in a releasable manner. A first stationary part 6 has anopening which can be closed by a second part 8. The first and secondpart 6, 8 can be moved relative to one another and in this way theopening can be at least partially closed. In the illustrated embodimentthe second part 8 is a door which can be turned around the first axis 10according to the first arrow 12. The open state of the door is shown bythe broken lines. A person can enter the interior of thespace-separating device 2 through the opening and can, for example,equip, maintain, or repair the machine 4. During operation of themachine 4, a person is not permitted or is not to remain within thespace-separating device 2.

For this purpose the device 1 has a first component 14 which is locatedon the first part 6 and a second component 16 which is located on thesecond part 8. The first component 14 has a receiver for a latch 18which is movably supported in the second component 16 and by means ofwhich the closed state of the space-separating device 2 shown in solidlines can be locked so that the space-separating device 2 cannot beopened in this state.

The locked state can be signaled by means of a safety switch by way of afirst connecting line 22 on a control device 20 which controls themachine 4 according to the filed control program by way of a secondconnecting line 24. Conversely, the machine 4, by way of the secondconnecting line 24, delivers feedback about the operating state to thecontrol device 20 and the control device 20 can control the device 1,for example, with respect to maintaining the locked state. The safetyswitch in the embodiment has a read head 26 which is located on thefirst component 14 and an actuator 28 which is located on the latch 18,signal exchange between the read head 26 and actuator 28 being possibleonly in the illustrated locked state.

The device 1 moreover has a holding element 30 which is located in thefirst component 14 in the embodiment and which can be pivoted around asecond axis 32 according to the arrow 34. The latch 18 can be blocked inthe illustrated locking position by the holding element 30. The holdingelement 30 and the latch 18 are positively engaged. In the embodimentthe holding element 30 for this purpose engages a recess in the latch18, the recess having a catch flank by which self-locking arisesrelative to the reset motion of the latch 18.

By means of a release element 36 (FIG. 2) the blocking of the latch 18can be neutralized, specifically, the holding element 30 can be liftedout of its position shown in FIG. 1. The blocking is neutralized by afirst actuating element which can be actuated from the interior of thespace-separating device 2 and which in the embodiment is formed by afirst knob 42 which can be turned around a third axis 38 according tothe third arrow 40. Following the neutralization of the blocking of thelatch 18, as the first knob continues to turn, the latch is retractedinto the second component 16 so that the locking of the closed state isalso neutralized and the second part 8 can be opened.

In one embodiment, the holding element 30 can be manually disengagedfrom the latch 18 only in this way, specifically not by the secondactuating element which is accessible from the outside of thespace-separating device 2 and which in the embodiment is formed by asecond knob 48 which can be turned around the fourth axis 44 accordingto the fourth arrow 46. With the second knob 48 the second part 8 can beclosed and by turning the second knob 48 the latch 18 can be extendedinto the illustrated locking position.

The space-separating device 2 in the embodiment is a protective cab or aprotective grating in which flat elements are attached to profiled rails50 which run perpendicular to the plane of the drawing of FIG. 1 and towhich the components 14, 16 of the device 1 can also be attached. As isapparent from the schematic of FIG. 1, the third axis 38 of the firstknob 42 and the fourth axis 44 of the second knob 48 which run parallelto one another have an offset to one another so that it is not necessaryto drill through the profile rails 52 into the interior of thespace-separating device 2 for passage of the fourth axis 44.

FIG. 2 shows a cutaway view of the embodiment of the device I which hasbeen enlarged compared to FIG. 1. The first component 14 is connected tothe first profile rails 50 and thus to the first part 6 (FIG. 1) byconnecting means which are not shown. Within the first component 14 theholding element 30 is mounted to be able to pivot around the second axis32 which runs perpendicular to the plane of the drawing and in theillustrated maintained locked state, with its projection 54 which hasbeen formed on the end side, it engages a recess 56 of the latch 18.

The essentially cylindrical latch 18 which in cross section can beshaped to be circular or essentially rectangular consists in thisembodiment of a plastic base part, with a metal insert part 58,specifically, a metal sheet which has been bent into a U-shape in crosssection. The insert part 58 forms the recess 56 and is used inparticular to accommodate the blocking forces. In a part which has beeninserted into the latch receiver 60 in the illustrated locked andblocked state, near the jacket surface on the latch 18 there is anactuator 28 which is made as a transponder and which can be read outfrom the read head 26 only in the illustrated position so that thelocked and closed state of the space-separating device 2 can besignaled.

The projection 54 of the holding element 30 and the recess 56 in theinsert part 58 each form a surface which are essentially parallel to oneanother and enclose a right angle with the direction of motion of thelatch 18 for unlocking. In an attempt to retract the latch 18 by turningthe second knob 48 around the fourth axis 44, this results in positivelocking between the latch 18 and the holding element 30 by which veryhigh holding .forces can be applied. The control device 20 or, forexample, a manual EMERGENCY OFF can route the holding element 30 out ofits holding position, for example, by an electromagnet 62 which islocated in the first component 14 being energized and thus the magnetarmature 64 coming into contact with the arm opposite the projection 54relative to the second axis 32 and the holding element 30 turningcounterclockwise in FIG. 2.

Regardless of such a controlled neutralization of holding, it ismoreover possible, by turning the first knob 42 around the third axis38, to move a displacement element 66 within the second component 16such that a release element 36 is turned clockwise around a fifth axis68 which runs perpendicular to the plane of the drawing in FIG. 2 and,in this way, with its section assigned to the holding element 30 comesinto contact with the holding element 30 and lifts it in the course ofrotary motion out of the recess 56 and thus neutralizes holding.Conversion of the rotary motion of the first knob 42 into linear motionof the displacement element 66 takes place by way of a coupling devicewhich has a first and second lever 82, 86 and which is shown in a sideview in FIG. 5. Coupling of the motion between the second knob 48 andthe latch 18 can take place in a similar manner.

When the first knob 42 is turning, the displacement element 66 and a pin70 located thereon are moved to the right in FIG. 2. In this way the pin70 comes into contact with the oblique surface 72 and the linear motionof the pin 70 is converted into rotary motion of the release element 36by interaction of the pin 70 with the oblique surface 72. The releaseelement 36 is made as a lever which has two arms relative to the fifthaxis 68, the action surface of the displacement element 66 lying on theside opposite the contact surface for the holding element 54 relative tothe fifth axis 68. The axis pin for supporting the release element 36 isformed by the latch 18 or is fixed on it.

FIG. 3 shows a cutaway view of the embodiment of device I correspondingto FIG. 2, however, here in the state in which the first knob 42 isturned around the third axis 38 so far that the pin 70 is movedcompletely along the oblique surface 72 and is held in a sector-shapedreceiver 74 of the release element 36. In this state the release element36 is turned maximally around the fifth axis 68 and thus the holdingelement 30 is lifted completely out of the recess 56 so that holding isneutralized. As the first knob 42 continues to turn and thus as thedisplacement element 66 continues to move, the pin 70 entrains therelease element 36 and by way of support on the fifth axis 68 also thelatch 18 and moves the latter in FIG. 3 to the right so that the latch18 emerges completely from the latch receiver 60 and accordingly thelocking is also neutralized.

If the holding element 30, for example, is monitored in its position bymeans of a photoelectric barrier or a Hall sensor, the state shown inFIG. 3 can be signaled such that there is no longer any holding. At thesame time it can also be signaled by way of the actuator 28 and the readhead 26 that the space-separating device 2 is still in a closed andlocked state.

FIG. 4 shows an enlargement comparable to FIGS. 2 and 3 in the state ofthe device 1 in which the latch 18 is retracted almost completely intothe second component 16 by complete tuning of the first knob 42. Thedisplacement element 66 is located like the latch 18 on its rear stop.Continued turning of the first knob 42 in the direction of rotationwhich has led to neutralization of blocking is no longer possible.

Based on the existing motion coupling, on the outside of thespace-separating device 2 the second knob 48 is now in its end positionwhich is opposite relative to FIG. 2 and has been turned back inparticular by turning the first knob 42. In the illustrated state thesecond part 8 (FIG. 1) can be opened relative to the first part 6. Theactuator 28 is no longer located in the read region of the read head 26so that the unlocked state can be signaled. If it is necessary oradvantageous that the closed state of the second part 8 still is to besignaled, an additional safety switch can be located, for example, onthe facing end sides of the first and second part 6, 8 whichindependently of the locking position of the latch 18 signals the closedposition of the second part 8.

For relocking from the position shown in FIG. 4 the latch 18 must againbe introduced into the latch receiver 60. This is not possible byturning the first knob 42 because the displacement element 66 in FIG. 4is indeed moved to the left, but there is no respective motion couplingwith the latch 18. This reliably prevents that a person located on theinside of the space-separating device 2 can move the latch 18 into itsposition which locks the closed state. Rather, for this purpose thesecond knob 48 must be turned and the latch 18 must be moved out of thesecond component 16.

On or near its face-side end, the latch has a bevel 76. With the latterthe latch 18 can lift the holding element 30 out of its position whichis shown in FIG. 4, in which the holding element 30 with its projection54 projects over the recess 56 into the latch receiver 60. When thelatch 18 has been fully inserted into the latch receiver 60, theprojection 54 in turn engages the recess 56 and blocks the latch 18 inits locking position. In this motion of the latch 18, based on themotion coupling between the release element 36 and the displacementelement 66, especially due to the contact of the sector-shaped receiver74 with the pin 70, the first knob 42 undergoes a reset motion until itagain assumes the initial position shown in FIG. 2.

Preferably, the holding element 30 integrally forms an action surface 90which is accessible from the outside of the device 1, in any case afterremoving a cover, by means of which holding can be manually neutralized,preferably with a suitable tool.

FIG. 5 shows a side view of the device 1 which is offset by 90° relativeto FIGS. 2 to 4, in particular of the component 16 from the direction ofthe position of the first knob 42. A coupling device is shown by meansof which the rotary motion of the first knob 42 is converted into linearmotion of the displacement element 66. FIG. 5 corresponds to theposition of the latch 18 in FIG. 2. A square 78 which can be turned by afirst knob 42 is nonrotatably connected by its shape to a driver shaft80 which in turn is nonrotatably connected to the first lever 82. At thearticulation point 84 which is formed, for example, by a pin, the firstlever 82 is connected to the second lever 86 which is in turn connectedto the displacement element 66 at a position spaced apart from thearticulation point 84, is articulated in particular at anotherarticulation point 88 on the displacement element 66. In this way, asthe first knob 42 turns around the third axis 38 which runsperpendicular to the plane of the drawing of FIG. 5, the displacementelement 66 is moved back and forth, there being motion coupling with therelease element 36 only in one direction.

1. A device (1) for maintaining a locked and closed state of aspace-separating device (2) in a releasable manner, in particular theprotective device of a machine (4) having a first part (6) with anopening and a second part (8), which parts can be moved relative to oneanother and in this way the opening can be at least partially closed,the device (1) having a latch (18) by means of which the closed state ofthe space-separating device (2) can be locked, a holding element (30) bymeans of which the latch (18) can be blocked in its locking position,and a release element (36) by means of which the blocking of the latch(18) can be neutralized, and the blocking of the latch (18) can beneutralized by a rotary motion of the release element (36) relative tothe latch (18).
 2. The device (1) according to claim 1, characterized inthat the release element (36) is a dual-arm lever which can be turnedaround an axis (68).
 3. The device (1) according to claim 2,characterized in that the first arm of the lever neutralizes theblocking of the latch (18) during rotation and the force for turning therelease element (36) can be delivered on the second arm.
 4. The device(1) according to claim 1, characterized in that the release element (36)can be turned by means of a displacement element (66) which is movablysupported in the device (1).
 5. The device (1) according to claim 4,characterized in that there is motion coupling between the displacementelement (66) and the release element (36) only in one direction ofmotion of the displacement element (66) which neutralizes the blockingof the latch (18).
 6. The device (1) according to claim 4, characterizedin that the release element (36) can be actuated by means of a firstknob (42) which is connected to the displacement element (66) by way ofa coupling device.
 7. The device according to claim 6, characterized inthat the coupling device converts the rotary motion of the first knob(42) into the linear motion of the displacement element (66).
 8. Thedevice (1) according to claim 6, characterized in that the couplingdevice has a first lever (82) and a second lever (86) which are hingedto one another at an articulation point (84), and that the first lever(82) is nonrotatably connected to the first knob (42) and the secondlever (86) is connected to the displacement element (66) at a positionat a distance from the articulation point (84).
 9. The device (1)according to claim 6, characterized in that the device (1) has a secondknob (48) by means of which the latch (18) can be moved into the lockedposition, and that the axes of rotation (38, 44) of the first and secondknob (42, 48) have an offset to one another.
 10. The device (1)according to claim 1, characterized in that following the rotary motionby means of which the blocking of the latch (18) can be neutralized, therelease element (36) together with the latch (18) can be moved and thusthe locking position of the latch (18) can be neutralized,
 11. Thedevice (1) according to claim 1, characterized in that the latch (18)and the holding element (30) positively engage one another in theposition which blocks the latch (18).
 12. The device (1) according toclaim 11, characterized in that the latch (18) has a recess (56) with acatch flank in which the holding element (30) catches in the positionwhich blocks the latch (18).
 13. The device (1) according to claim 1,characterized in that the device (1) has a first sensor by means ofwhich the position of the latch (18) which locks the closed state of thespace-separating device (2) can be signaled.
 14. The device (1)according to claim 13, characterized in that the first sensor is asafety switch which wirelessly transmits signals.
 15. The device (1)according to claim 13, characterized in that the first sensor has a readhead (26) and an actuator (28) which interacts with the read head (26),preferably a transponder which is located on the latch (18), and thatonly in the position of the latch (18) which locks the closed state ofthe space-separating device (2) is signal transmission between the readhead (26) and the transponder (28) possible.
 16. The device (1)according to claim 1, characterized in that the device (1) has a secondsensor by means of which the position of the holding element (30) whichblocks the latch (18) can be signaled.